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NetBSD/sys/kern/vfs_subr.c
jmmv 2a3e5eeb7c Apply the NFS exports list rototill patch: 
- Remove all NFS related stuff from file system specific code.
- Drop the vfs_checkexp hook and generalize it in the new nfs_check_export
  function, thus removing redundancy from all file systems.
- Move all NFS export-related stuff from kern/vfs_subr.c to the new
  file sys/nfs/nfs_export.c.  The former was becoming large and its code
  is always compiled, regardless of the build options.  Using the latter,
  the code is only compiled in when NFSSERVER is enabled.  While doing this,
  also make some functions in nfs_subs.c conditional to NFSSERVER.
- Add a new command in nfssvc(2), called NFSSVC_SETEXPORTSLIST, that takes a
  path and a set of export entries.  At the moment it can only clear the
  exports list or append entries, one by one, but it is done in a way that
  allows setting the whole set of entries atomically in the future (see the
  comment in mountd_set_exports_list or in doc/TODO).
- Change mountd(8) to use the nfssvc(2) system call instead of mount(2) so
  that it becomes file system agnostic.  In fact, all this whole thing was
  done to remove a 'XXX' block from this utility!
- Change the mount*, newfs and fsck* userland utilities to not deal with NFS
  exports initialization; done internally by the kernel when initializing
  the NFS support for each file system.
- Implement an interface for VFS (called VFS hooks) so that several kernel
  subsystems can run arbitrary code upon receipt of specific VFS events.
  At the moment, this only provides support for unmount and is used to
  destroy NFS exports lists from the file systems being unmounted, though it
  has room for extension.

Thanks go to yamt@, chs@, thorpej@, wrstuden@ and others for their comments
and advice in the development of this patch.
2005-09-23 12:10:31 +00:00

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/* $NetBSD: vfs_subr.c,v 1.254 2005/09/23 12:10:33 jmmv Exp $ */
/*-
* Copyright (c) 1997, 1998, 2004, 2005 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center.
* This code is derived from software contributed to The NetBSD Foundation
* by Charles M. Hannum.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)vfs_subr.c 8.13 (Berkeley) 4/18/94
*/
/*
* External virtual filesystem routines
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: vfs_subr.c,v 1.254 2005/09/23 12:10:33 jmmv Exp $");
#include "opt_inet.h"
#include "opt_ddb.h"
#include "opt_compat_netbsd.h"
#include "opt_compat_43.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/kernel.h>
#include <sys/mount.h>
#include <sys/fcntl.h>
#include <sys/vnode.h>
#include <sys/stat.h>
#include <sys/namei.h>
#include <sys/ucred.h>
#include <sys/buf.h>
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/domain.h>
#include <sys/mbuf.h>
#include <sys/sa.h>
#include <sys/syscallargs.h>
#include <sys/device.h>
#include <sys/filedesc.h>
#include <miscfs/specfs/specdev.h>
#include <miscfs/genfs/genfs.h>
#include <miscfs/syncfs/syncfs.h>
#include <uvm/uvm.h>
#include <uvm/uvm_ddb.h>
#include <sys/sysctl.h>
const enum vtype iftovt_tab[16] = {
VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD,
};
const int vttoif_tab[9] = {
0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK,
S_IFSOCK, S_IFIFO, S_IFMT,
};
int doforce = 1; /* 1 => permit forcible unmounting */
int prtactive = 0; /* 1 => print out reclaim of active vnodes */
extern int dovfsusermount; /* 1 => permit any user to mount filesystems */
/*
* Insq/Remq for the vnode usage lists.
*/
#define bufinsvn(bp, dp) LIST_INSERT_HEAD(dp, bp, b_vnbufs)
#define bufremvn(bp) { \
LIST_REMOVE(bp, b_vnbufs); \
(bp)->b_vnbufs.le_next = NOLIST; \
}
/* TAILQ_HEAD(freelst, vnode) vnode_free_list = vnode free list (in vnode.h) */
struct freelst vnode_free_list = TAILQ_HEAD_INITIALIZER(vnode_free_list);
struct freelst vnode_hold_list = TAILQ_HEAD_INITIALIZER(vnode_hold_list);
struct mntlist mountlist = /* mounted filesystem list */
CIRCLEQ_HEAD_INITIALIZER(mountlist);
struct vfs_list_head vfs_list = /* vfs list */
LIST_HEAD_INITIALIZER(vfs_list);
struct simplelock mountlist_slock = SIMPLELOCK_INITIALIZER;
static struct simplelock mntid_slock = SIMPLELOCK_INITIALIZER;
struct simplelock mntvnode_slock = SIMPLELOCK_INITIALIZER;
struct simplelock vnode_free_list_slock = SIMPLELOCK_INITIALIZER;
struct simplelock spechash_slock = SIMPLELOCK_INITIALIZER;
/* XXX - gross; single global lock to protect v_numoutput */
struct simplelock global_v_numoutput_slock = SIMPLELOCK_INITIALIZER;
/*
* These define the root filesystem and device.
*/
struct mount *rootfs;
struct vnode *rootvnode;
struct device *root_device; /* root device */
POOL_INIT(vnode_pool, sizeof(struct vnode), 0, 0, 0, "vnodepl",
&pool_allocator_nointr);
MALLOC_DEFINE(M_VNODE, "vnodes", "Dynamically allocated vnodes");
/*
* Local declarations.
*/
void insmntque(struct vnode *, struct mount *);
int getdevvp(dev_t, struct vnode **, enum vtype);
void vclean(struct vnode *, int, struct proc *);
static struct vnode *getcleanvnode(struct proc *);
#ifdef DEBUG
void printlockedvnodes(void);
#endif
/*
* Initialize the vnode management data structures.
*/
void
vntblinit(void)
{
/*
* Initialize the filesystem syncer.
*/
vn_initialize_syncerd();
}
int
vfs_drainvnodes(long target, struct proc *p)
{
simple_lock(&vnode_free_list_slock);
while (numvnodes > target) {
struct vnode *vp;
vp = getcleanvnode(p);
if (vp == NULL)
return EBUSY; /* give up */
pool_put(&vnode_pool, vp);
simple_lock(&vnode_free_list_slock);
numvnodes--;
}
simple_unlock(&vnode_free_list_slock);
return 0;
}
/*
* grab a vnode from freelist and clean it.
*/
struct vnode *
getcleanvnode(struct proc *p)
{
struct vnode *vp;
struct mount *mp;
struct freelst *listhd;
LOCK_ASSERT(simple_lock_held(&vnode_free_list_slock));
listhd = &vnode_free_list;
try_nextlist:
TAILQ_FOREACH(vp, listhd, v_freelist) {
if (!simple_lock_try(&vp->v_interlock))
continue;
/*
* as our lwp might hold the underlying vnode locked,
* don't try to reclaim the VLAYER vnode if it's locked.
*/
if ((vp->v_flag & VXLOCK) == 0 &&
((vp->v_flag & VLAYER) == 0 || VOP_ISLOCKED(vp) == 0)) {
if (vn_start_write(vp, &mp, V_NOWAIT) == 0)
break;
}
mp = NULL;
simple_unlock(&vp->v_interlock);
}
if (vp == NULLVP) {
if (listhd == &vnode_free_list) {
listhd = &vnode_hold_list;
goto try_nextlist;
}
simple_unlock(&vnode_free_list_slock);
return NULLVP;
}
if (vp->v_usecount)
panic("free vnode isn't, vp %p", vp);
TAILQ_REMOVE(listhd, vp, v_freelist);
/* see comment on why 0xdeadb is set at end of vgone (below) */
vp->v_freelist.tqe_prev = (struct vnode **)0xdeadb;
simple_unlock(&vnode_free_list_slock);
vp->v_lease = NULL;
if (vp->v_type != VBAD)
vgonel(vp, p);
else
simple_unlock(&vp->v_interlock);
vn_finished_write(mp, 0);
#ifdef DIAGNOSTIC
if (vp->v_data || vp->v_uobj.uo_npages ||
TAILQ_FIRST(&vp->v_uobj.memq))
panic("cleaned vnode isn't, vp %p", vp);
if (vp->v_numoutput)
panic("clean vnode has pending I/O's, vp %p", vp);
#endif
KASSERT((vp->v_flag & VONWORKLST) == 0);
return vp;
}
/*
* Mark a mount point as busy. Used to synchronize access and to delay
* unmounting. Interlock is not released on failure.
*/
int
vfs_busy(struct mount *mp, int flags, struct simplelock *interlkp)
{
int lkflags;
while (mp->mnt_iflag & IMNT_UNMOUNT) {
int gone, n;
if (flags & LK_NOWAIT)
return (ENOENT);
if ((flags & LK_RECURSEFAIL) && mp->mnt_unmounter != NULL
&& mp->mnt_unmounter == curproc)
return (EDEADLK);
if (interlkp)
simple_unlock(interlkp);
/*
* Since all busy locks are shared except the exclusive
* lock granted when unmounting, the only place that a
* wakeup needs to be done is at the release of the
* exclusive lock at the end of dounmount.
*/
simple_lock(&mp->mnt_slock);
mp->mnt_wcnt++;
ltsleep((caddr_t)mp, PVFS, "vfs_busy", 0, &mp->mnt_slock);
n = --mp->mnt_wcnt;
simple_unlock(&mp->mnt_slock);
gone = mp->mnt_iflag & IMNT_GONE;
if (n == 0)
wakeup(&mp->mnt_wcnt);
if (interlkp)
simple_lock(interlkp);
if (gone)
return (ENOENT);
}
lkflags = LK_SHARED;
if (interlkp)
lkflags |= LK_INTERLOCK;
if (lockmgr(&mp->mnt_lock, lkflags, interlkp))
panic("vfs_busy: unexpected lock failure");
return (0);
}
/*
* Free a busy filesystem.
*/
void
vfs_unbusy(struct mount *mp)
{
lockmgr(&mp->mnt_lock, LK_RELEASE, NULL);
}
/*
* Lookup a filesystem type, and if found allocate and initialize
* a mount structure for it.
*
* Devname is usually updated by mount(8) after booting.
*/
int
vfs_rootmountalloc(const char *fstypename, const char *devname,
struct mount **mpp)
{
struct vfsops *vfsp = NULL;
struct mount *mp;
LIST_FOREACH(vfsp, &vfs_list, vfs_list)
if (!strncmp(vfsp->vfs_name, fstypename, MFSNAMELEN))
break;
if (vfsp == NULL)
return (ENODEV);
mp = malloc((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK);
memset((char *)mp, 0, (u_long)sizeof(struct mount));
lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, 0);
simple_lock_init(&mp->mnt_slock);
(void)vfs_busy(mp, LK_NOWAIT, 0);
LIST_INIT(&mp->mnt_vnodelist);
mp->mnt_op = vfsp;
mp->mnt_flag = MNT_RDONLY;
mp->mnt_vnodecovered = NULLVP;
mp->mnt_leaf = mp;
vfsp->vfs_refcount++;
strncpy(mp->mnt_stat.f_fstypename, vfsp->vfs_name, MFSNAMELEN);
mp->mnt_stat.f_mntonname[0] = '/';
(void) copystr(devname, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, 0);
*mpp = mp;
return (0);
}
/*
* Lookup a mount point by filesystem identifier.
*/
struct mount *
vfs_getvfs(fsid_t *fsid)
{
struct mount *mp;
simple_lock(&mountlist_slock);
CIRCLEQ_FOREACH(mp, &mountlist, mnt_list) {
if (mp->mnt_stat.f_fsidx.__fsid_val[0] == fsid->__fsid_val[0] &&
mp->mnt_stat.f_fsidx.__fsid_val[1] == fsid->__fsid_val[1]) {
simple_unlock(&mountlist_slock);
return (mp);
}
}
simple_unlock(&mountlist_slock);
return ((struct mount *)0);
}
/*
* Get a new unique fsid
*/
void
vfs_getnewfsid(struct mount *mp)
{
static u_short xxxfs_mntid;
fsid_t tfsid;
int mtype;
simple_lock(&mntid_slock);
mtype = makefstype(mp->mnt_op->vfs_name);
mp->mnt_stat.f_fsidx.__fsid_val[0] = makedev(mtype, 0);
mp->mnt_stat.f_fsidx.__fsid_val[1] = mtype;
mp->mnt_stat.f_fsid = mp->mnt_stat.f_fsidx.__fsid_val[0];
if (xxxfs_mntid == 0)
++xxxfs_mntid;
tfsid.__fsid_val[0] = makedev(mtype & 0xff, xxxfs_mntid);
tfsid.__fsid_val[1] = mtype;
if (!CIRCLEQ_EMPTY(&mountlist)) {
while (vfs_getvfs(&tfsid)) {
tfsid.__fsid_val[0]++;
xxxfs_mntid++;
}
}
mp->mnt_stat.f_fsidx.__fsid_val[0] = tfsid.__fsid_val[0];
mp->mnt_stat.f_fsid = mp->mnt_stat.f_fsidx.__fsid_val[0];
simple_unlock(&mntid_slock);
}
/*
* Make a 'unique' number from a mount type name.
*/
long
makefstype(const char *type)
{
long rv;
for (rv = 0; *type; type++) {
rv <<= 2;
rv ^= *type;
}
return rv;
}
/*
* Set vnode attributes to VNOVAL
*/
void
vattr_null(struct vattr *vap)
{
vap->va_type = VNON;
/*
* Assign individually so that it is safe even if size and
* sign of each member are varied.
*/
vap->va_mode = VNOVAL;
vap->va_nlink = VNOVAL;
vap->va_uid = VNOVAL;
vap->va_gid = VNOVAL;
vap->va_fsid = VNOVAL;
vap->va_fileid = VNOVAL;
vap->va_size = VNOVAL;
vap->va_blocksize = VNOVAL;
vap->va_atime.tv_sec =
vap->va_mtime.tv_sec =
vap->va_ctime.tv_sec =
vap->va_birthtime.tv_sec = VNOVAL;
vap->va_atime.tv_nsec =
vap->va_mtime.tv_nsec =
vap->va_ctime.tv_nsec =
vap->va_birthtime.tv_nsec = VNOVAL;
vap->va_gen = VNOVAL;
vap->va_flags = VNOVAL;
vap->va_rdev = VNOVAL;
vap->va_bytes = VNOVAL;
vap->va_vaflags = 0;
}
/*
* Routines having to do with the management of the vnode table.
*/
extern int (**dead_vnodeop_p)(void *);
long numvnodes;
/*
* Return the next vnode from the free list.
*/
int
getnewvnode(enum vtagtype tag, struct mount *mp, int (**vops)(void *),
struct vnode **vpp)
{
extern struct uvm_pagerops uvm_vnodeops;
struct uvm_object *uobj;
struct proc *p = curproc; /* XXX */
static int toggle;
struct vnode *vp;
int error = 0, tryalloc;
try_again:
if (mp) {
/*
* Mark filesystem busy while we're creating a vnode.
* If unmount is in progress, this will wait; if the
* unmount succeeds (only if umount -f), this will
* return an error. If the unmount fails, we'll keep
* going afterwards.
* (This puts the per-mount vnode list logically under
* the protection of the vfs_busy lock).
*/
error = vfs_busy(mp, LK_RECURSEFAIL, 0);
if (error && error != EDEADLK)
return error;
}
/*
* We must choose whether to allocate a new vnode or recycle an
* existing one. The criterion for allocating a new one is that
* the total number of vnodes is less than the number desired or
* there are no vnodes on either free list. Generally we only
* want to recycle vnodes that have no buffers associated with
* them, so we look first on the vnode_free_list. If it is empty,
* we next consider vnodes with referencing buffers on the
* vnode_hold_list. The toggle ensures that half the time we
* will use a buffer from the vnode_hold_list, and half the time
* we will allocate a new one unless the list has grown to twice
* the desired size. We are reticent to recycle vnodes from the
* vnode_hold_list because we will lose the identity of all its
* referencing buffers.
*/
vp = NULL;
simple_lock(&vnode_free_list_slock);
toggle ^= 1;
if (numvnodes > 2 * desiredvnodes)
toggle = 0;
tryalloc = numvnodes < desiredvnodes ||
(TAILQ_FIRST(&vnode_free_list) == NULL &&
(TAILQ_FIRST(&vnode_hold_list) == NULL || toggle));
if (tryalloc &&
(vp = pool_get(&vnode_pool, PR_NOWAIT)) != NULL) {
numvnodes++;
simple_unlock(&vnode_free_list_slock);
memset(vp, 0, sizeof(*vp));
UVM_OBJ_INIT(&vp->v_uobj, &uvm_vnodeops, 1);
/*
* done by memset() above.
* LIST_INIT(&vp->v_nclist);
* LIST_INIT(&vp->v_dnclist);
*/
} else {
vp = getcleanvnode(p);
/*
* Unless this is a bad time of the month, at most
* the first NCPUS items on the free list are
* locked, so this is close enough to being empty.
*/
if (vp == NULLVP) {
if (mp && error != EDEADLK)
vfs_unbusy(mp);
if (tryalloc) {
printf("WARNING: unable to allocate new "
"vnode, retrying...\n");
(void) tsleep(&lbolt, PRIBIO, "newvn", hz);
goto try_again;
}
tablefull("vnode", "increase kern.maxvnodes or NVNODE");
*vpp = 0;
return (ENFILE);
}
vp->v_usecount = 1;
vp->v_flag = 0;
vp->v_socket = NULL;
}
vp->v_type = VNON;
vp->v_vnlock = &vp->v_lock;
lockinit(vp->v_vnlock, PVFS, "vnlock", 0, 0);
KASSERT(LIST_EMPTY(&vp->v_nclist));
KASSERT(LIST_EMPTY(&vp->v_dnclist));
vp->v_tag = tag;
vp->v_op = vops;
insmntque(vp, mp);
*vpp = vp;
vp->v_data = 0;
simple_lock_init(&vp->v_interlock);
/*
* initialize uvm_object within vnode.
*/
uobj = &vp->v_uobj;
KASSERT(uobj->pgops == &uvm_vnodeops);
KASSERT(uobj->uo_npages == 0);
KASSERT(TAILQ_FIRST(&uobj->memq) == NULL);
vp->v_size = VSIZENOTSET;
if (mp && error != EDEADLK)
vfs_unbusy(mp);
return (0);
}
/*
* This is really just the reverse of getnewvnode(). Needed for
* VFS_VGET functions who may need to push back a vnode in case
* of a locking race.
*/
void
ungetnewvnode(struct vnode *vp)
{
#ifdef DIAGNOSTIC
if (vp->v_usecount != 1)
panic("ungetnewvnode: busy vnode");
#endif
vp->v_usecount--;
insmntque(vp, NULL);
vp->v_type = VBAD;
simple_lock(&vp->v_interlock);
/*
* Insert at head of LRU list
*/
simple_lock(&vnode_free_list_slock);
if (vp->v_holdcnt > 0)
TAILQ_INSERT_HEAD(&vnode_hold_list, vp, v_freelist);
else
TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
simple_unlock(&vnode_free_list_slock);
simple_unlock(&vp->v_interlock);
}
/*
* Move a vnode from one mount queue to another.
*/
void
insmntque(struct vnode *vp, struct mount *mp)
{
#ifdef DIAGNOSTIC
if ((mp != NULL) &&
(mp->mnt_iflag & IMNT_UNMOUNT) &&
!(mp->mnt_flag & MNT_SOFTDEP) &&
vp->v_tag != VT_VFS) {
panic("insmntque into dying filesystem");
}
#endif
simple_lock(&mntvnode_slock);
/*
* Delete from old mount point vnode list, if on one.
*/
if (vp->v_mount != NULL)
LIST_REMOVE(vp, v_mntvnodes);
/*
* Insert into list of vnodes for the new mount point, if available.
*/
if ((vp->v_mount = mp) != NULL)
LIST_INSERT_HEAD(&mp->mnt_vnodelist, vp, v_mntvnodes);
simple_unlock(&mntvnode_slock);
}
/*
* Update outstanding I/O count and do wakeup if requested.
*/
void
vwakeup(struct buf *bp)
{
struct vnode *vp;
if ((vp = bp->b_vp) != NULL) {
/* XXX global lock hack
* can't use v_interlock here since this is called
* in interrupt context from biodone().
*/
simple_lock(&global_v_numoutput_slock);
if (--vp->v_numoutput < 0)
panic("vwakeup: neg numoutput, vp %p", vp);
if ((vp->v_flag & VBWAIT) && vp->v_numoutput <= 0) {
vp->v_flag &= ~VBWAIT;
wakeup((caddr_t)&vp->v_numoutput);
}
simple_unlock(&global_v_numoutput_slock);
}
}
/*
* Flush out and invalidate all buffers associated with a vnode.
* Called with the underlying vnode locked, which should prevent new dirty
* buffers from being queued.
*/
int
vinvalbuf(struct vnode *vp, int flags, struct ucred *cred, struct proc *p,
int slpflag, int slptimeo)
{
struct buf *bp, *nbp;
int s, error;
int flushflags = PGO_ALLPAGES | PGO_FREE | PGO_SYNCIO |
(flags & V_SAVE ? PGO_CLEANIT : 0);
/* XXXUBC this doesn't look at flags or slp* */
simple_lock(&vp->v_interlock);
error = VOP_PUTPAGES(vp, 0, 0, flushflags);
if (error) {
return error;
}
if (flags & V_SAVE) {
error = VOP_FSYNC(vp, cred, FSYNC_WAIT|FSYNC_RECLAIM, 0, 0, p);
if (error)
return (error);
#ifdef DIAGNOSTIC
s = splbio();
if (vp->v_numoutput > 0 || !LIST_EMPTY(&vp->v_dirtyblkhd))
panic("vinvalbuf: dirty bufs, vp %p", vp);
splx(s);
#endif
}
s = splbio();
restart:
for (bp = LIST_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) {
nbp = LIST_NEXT(bp, b_vnbufs);
simple_lock(&bp->b_interlock);
if (bp->b_flags & B_BUSY) {
bp->b_flags |= B_WANTED;
error = ltsleep((caddr_t)bp,
slpflag | (PRIBIO + 1) | PNORELOCK,
"vinvalbuf", slptimeo, &bp->b_interlock);
if (error) {
splx(s);
return (error);
}
goto restart;
}
bp->b_flags |= B_BUSY | B_INVAL | B_VFLUSH;
simple_unlock(&bp->b_interlock);
brelse(bp);
}
for (bp = LIST_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
nbp = LIST_NEXT(bp, b_vnbufs);
simple_lock(&bp->b_interlock);
if (bp->b_flags & B_BUSY) {
bp->b_flags |= B_WANTED;
error = ltsleep((caddr_t)bp,
slpflag | (PRIBIO + 1) | PNORELOCK,
"vinvalbuf", slptimeo, &bp->b_interlock);
if (error) {
splx(s);
return (error);
}
goto restart;
}
/*
* XXX Since there are no node locks for NFS, I believe
* there is a slight chance that a delayed write will
* occur while sleeping just above, so check for it.
*/
if ((bp->b_flags & B_DELWRI) && (flags & V_SAVE)) {
#ifdef DEBUG
printf("buffer still DELWRI\n");
#endif
bp->b_flags |= B_BUSY | B_VFLUSH;
simple_unlock(&bp->b_interlock);
VOP_BWRITE(bp);
goto restart;
}
bp->b_flags |= B_BUSY | B_INVAL | B_VFLUSH;
simple_unlock(&bp->b_interlock);
brelse(bp);
}
#ifdef DIAGNOSTIC
if (!LIST_EMPTY(&vp->v_cleanblkhd) || !LIST_EMPTY(&vp->v_dirtyblkhd))
panic("vinvalbuf: flush failed, vp %p", vp);
#endif
splx(s);
return (0);
}
/*
* Destroy any in core blocks past the truncation length.
* Called with the underlying vnode locked, which should prevent new dirty
* buffers from being queued.
*/
int
vtruncbuf(struct vnode *vp, daddr_t lbn, int slpflag, int slptimeo)
{
struct buf *bp, *nbp;
int s, error;
voff_t off;
off = round_page((voff_t)lbn << vp->v_mount->mnt_fs_bshift);
simple_lock(&vp->v_interlock);
error = VOP_PUTPAGES(vp, off, 0, PGO_FREE | PGO_SYNCIO);
if (error) {
return error;
}
s = splbio();
restart:
for (bp = LIST_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) {
nbp = LIST_NEXT(bp, b_vnbufs);
if (bp->b_lblkno < lbn)
continue;
simple_lock(&bp->b_interlock);
if (bp->b_flags & B_BUSY) {
bp->b_flags |= B_WANTED;
error = ltsleep(bp, slpflag | (PRIBIO + 1) | PNORELOCK,
"vtruncbuf", slptimeo, &bp->b_interlock);
if (error) {
splx(s);
return (error);
}
goto restart;
}
bp->b_flags |= B_BUSY | B_INVAL | B_VFLUSH;
simple_unlock(&bp->b_interlock);
brelse(bp);
}
for (bp = LIST_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
nbp = LIST_NEXT(bp, b_vnbufs);
if (bp->b_lblkno < lbn)
continue;
simple_lock(&bp->b_interlock);
if (bp->b_flags & B_BUSY) {
bp->b_flags |= B_WANTED;
error = ltsleep(bp, slpflag | (PRIBIO + 1) | PNORELOCK,
"vtruncbuf", slptimeo, &bp->b_interlock);
if (error) {
splx(s);
return (error);
}
goto restart;
}
bp->b_flags |= B_BUSY | B_INVAL | B_VFLUSH;
simple_unlock(&bp->b_interlock);
brelse(bp);
}
splx(s);
return (0);
}
void
vflushbuf(struct vnode *vp, int sync)
{
struct buf *bp, *nbp;
int flags = PGO_CLEANIT | PGO_ALLPAGES | (sync ? PGO_SYNCIO : 0);
int s;
simple_lock(&vp->v_interlock);
(void) VOP_PUTPAGES(vp, 0, 0, flags);
loop:
s = splbio();
for (bp = LIST_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
nbp = LIST_NEXT(bp, b_vnbufs);
simple_lock(&bp->b_interlock);
if ((bp->b_flags & B_BUSY)) {
simple_unlock(&bp->b_interlock);
continue;
}
if ((bp->b_flags & B_DELWRI) == 0)
panic("vflushbuf: not dirty, bp %p", bp);
bp->b_flags |= B_BUSY | B_VFLUSH;
simple_unlock(&bp->b_interlock);
splx(s);
/*
* Wait for I/O associated with indirect blocks to complete,
* since there is no way to quickly wait for them below.
*/
if (bp->b_vp == vp || sync == 0)
(void) bawrite(bp);
else
(void) bwrite(bp);
goto loop;
}
if (sync == 0) {
splx(s);
return;
}
simple_lock(&global_v_numoutput_slock);
while (vp->v_numoutput) {
vp->v_flag |= VBWAIT;
ltsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "vflushbuf", 0,
&global_v_numoutput_slock);
}
simple_unlock(&global_v_numoutput_slock);
splx(s);
if (!LIST_EMPTY(&vp->v_dirtyblkhd)) {
vprint("vflushbuf: dirty", vp);
goto loop;
}
}
/*
* Associate a buffer with a vnode.
*/
void
bgetvp(struct vnode *vp, struct buf *bp)
{
int s;
if (bp->b_vp)
panic("bgetvp: not free, bp %p", bp);
VHOLD(vp);
s = splbio();
bp->b_vp = vp;
if (vp->v_type == VBLK || vp->v_type == VCHR)
bp->b_dev = vp->v_rdev;
else
bp->b_dev = NODEV;
/*
* Insert onto list for new vnode.
*/
bufinsvn(bp, &vp->v_cleanblkhd);
splx(s);
}
/*
* Disassociate a buffer from a vnode.
*/
void
brelvp(struct buf *bp)
{
struct vnode *vp;
int s;
if (bp->b_vp == NULL)
panic("brelvp: vp NULL, bp %p", bp);
s = splbio();
vp = bp->b_vp;
/*
* Delete from old vnode list, if on one.
*/
if (LIST_NEXT(bp, b_vnbufs) != NOLIST)
bufremvn(bp);
if (TAILQ_EMPTY(&vp->v_uobj.memq) && (vp->v_flag & VONWORKLST) &&
LIST_FIRST(&vp->v_dirtyblkhd) == NULL) {
vp->v_flag &= ~(VWRITEMAPDIRTY|VONWORKLST);
LIST_REMOVE(vp, v_synclist);
}
bp->b_vp = NULL;
HOLDRELE(vp);
splx(s);
}
/*
* Reassign a buffer from one vnode to another.
* Used to assign file specific control information
* (indirect blocks) to the vnode to which they belong.
*
* This function must be called at splbio().
*/
void
reassignbuf(struct buf *bp, struct vnode *newvp)
{
struct buflists *listheadp;
int delayx;
/*
* Delete from old vnode list, if on one.
*/
if (LIST_NEXT(bp, b_vnbufs) != NOLIST)
bufremvn(bp);
/*
* If dirty, put on list of dirty buffers;
* otherwise insert onto list of clean buffers.
*/
if ((bp->b_flags & B_DELWRI) == 0) {
listheadp = &newvp->v_cleanblkhd;
if (TAILQ_EMPTY(&newvp->v_uobj.memq) &&
(newvp->v_flag & VONWORKLST) &&
LIST_FIRST(&newvp->v_dirtyblkhd) == NULL) {
newvp->v_flag &= ~(VWRITEMAPDIRTY|VONWORKLST);
LIST_REMOVE(newvp, v_synclist);
}
} else {
listheadp = &newvp->v_dirtyblkhd;
if ((newvp->v_flag & VONWORKLST) == 0) {
switch (newvp->v_type) {
case VDIR:
delayx = dirdelay;
break;
case VBLK:
if (newvp->v_specmountpoint != NULL) {
delayx = metadelay;
break;
}
/* fall through */
default:
delayx = filedelay;
break;
}
if (!newvp->v_mount ||
(newvp->v_mount->mnt_flag & MNT_ASYNC) == 0)
vn_syncer_add_to_worklist(newvp, delayx);
}
}
bufinsvn(bp, listheadp);
}
/*
* Create a vnode for a block device.
* Used for root filesystem and swap areas.
* Also used for memory file system special devices.
*/
int
bdevvp(dev_t dev, struct vnode **vpp)
{
return (getdevvp(dev, vpp, VBLK));
}
/*
* Create a vnode for a character device.
* Used for kernfs and some console handling.
*/
int
cdevvp(dev_t dev, struct vnode **vpp)
{
return (getdevvp(dev, vpp, VCHR));
}
/*
* Create a vnode for a device.
* Used by bdevvp (block device) for root file system etc.,
* and by cdevvp (character device) for console and kernfs.
*/
int
getdevvp(dev_t dev, struct vnode **vpp, enum vtype type)
{
struct vnode *vp;
struct vnode *nvp;
int error;
if (dev == NODEV) {
*vpp = NULLVP;
return (0);
}
error = getnewvnode(VT_NON, NULL, spec_vnodeop_p, &nvp);
if (error) {
*vpp = NULLVP;
return (error);
}
vp = nvp;
vp->v_type = type;
if ((nvp = checkalias(vp, dev, NULL)) != 0) {
vput(vp);
vp = nvp;
}
*vpp = vp;
return (0);
}
/*
* Check to see if the new vnode represents a special device
* for which we already have a vnode (either because of
* bdevvp() or because of a different vnode representing
* the same block device). If such an alias exists, deallocate
* the existing contents and return the aliased vnode. The
* caller is responsible for filling it with its new contents.
*/
struct vnode *
checkalias(struct vnode *nvp, dev_t nvp_rdev, struct mount *mp)
{
struct proc *p = curproc; /* XXX */
struct vnode *vp;
struct vnode **vpp;
if (nvp->v_type != VBLK && nvp->v_type != VCHR)
return (NULLVP);
vpp = &speclisth[SPECHASH(nvp_rdev)];
loop:
simple_lock(&spechash_slock);
for (vp = *vpp; vp; vp = vp->v_specnext) {
if (nvp_rdev != vp->v_rdev || nvp->v_type != vp->v_type)
continue;
/*
* Alias, but not in use, so flush it out.
*/
simple_lock(&vp->v_interlock);
simple_unlock(&spechash_slock);
if (vp->v_usecount == 0) {
vgonel(vp, p);
goto loop;
}
/*
* What we're interested to know here is if someone else has
* removed this vnode from the device hash list while we were
* waiting. This can only happen if vclean() did it, and
* this requires the vnode to be locked. Therefore, we use
* LK_SLEEPFAIL and retry.
*/
if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK | LK_SLEEPFAIL))
goto loop;
simple_lock(&spechash_slock);
break;
}
if (vp == NULL || vp->v_tag != VT_NON || vp->v_type != VBLK) {
MALLOC(nvp->v_specinfo, struct specinfo *,
sizeof(struct specinfo), M_VNODE, M_NOWAIT);
/* XXX Erg. */
if (nvp->v_specinfo == NULL) {
simple_unlock(&spechash_slock);
uvm_wait("checkalias");
goto loop;
}
nvp->v_rdev = nvp_rdev;
nvp->v_hashchain = vpp;
nvp->v_specnext = *vpp;
nvp->v_specmountpoint = NULL;
simple_unlock(&spechash_slock);
nvp->v_speclockf = NULL;
simple_lock_init(&nvp->v_spec_cow_slock);
SLIST_INIT(&nvp->v_spec_cow_head);
nvp->v_spec_cow_req = 0;
nvp->v_spec_cow_count = 0;
*vpp = nvp;
if (vp != NULLVP) {
nvp->v_flag |= VALIASED;
vp->v_flag |= VALIASED;
vput(vp);
}
return (NULLVP);
}
simple_unlock(&spechash_slock);
VOP_UNLOCK(vp, 0);
simple_lock(&vp->v_interlock);
vclean(vp, 0, p);
vp->v_op = nvp->v_op;
vp->v_tag = nvp->v_tag;
vp->v_vnlock = &vp->v_lock;
lockinit(vp->v_vnlock, PVFS, "vnlock", 0, 0);
nvp->v_type = VNON;
insmntque(vp, mp);
return (vp);
}
/*
* Grab a particular vnode from the free list, increment its
* reference count and lock it. If the vnode lock bit is set the
* vnode is being eliminated in vgone. In that case, we can not
* grab the vnode, so the process is awakened when the transition is
* completed, and an error returned to indicate that the vnode is no
* longer usable (possibly having been changed to a new file system type).
*/
int
vget(struct vnode *vp, int flags)
{
int error;
/*
* If the vnode is in the process of being cleaned out for
* another use, we wait for the cleaning to finish and then
* return failure. Cleaning is determined by checking that
* the VXLOCK flag is set.
*/
if ((flags & LK_INTERLOCK) == 0)
simple_lock(&vp->v_interlock);
if (vp->v_flag & VXLOCK) {
if (flags & LK_NOWAIT) {
simple_unlock(&vp->v_interlock);
return EBUSY;
}
vp->v_flag |= VXWANT;
ltsleep(vp, PINOD|PNORELOCK, "vget", 0, &vp->v_interlock);
return (ENOENT);
}
if (vp->v_usecount == 0) {
simple_lock(&vnode_free_list_slock);
if (vp->v_holdcnt > 0)
TAILQ_REMOVE(&vnode_hold_list, vp, v_freelist);
else
TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
simple_unlock(&vnode_free_list_slock);
}
vp->v_usecount++;
#ifdef DIAGNOSTIC
if (vp->v_usecount == 0) {
vprint("vget", vp);
panic("vget: usecount overflow, vp %p", vp);
}
#endif
if (flags & LK_TYPE_MASK) {
if ((error = vn_lock(vp, flags | LK_INTERLOCK))) {
/*
* must expand vrele here because we do not want
* to call VOP_INACTIVE if the reference count
* drops back to zero since it was never really
* active. We must remove it from the free list
* before sleeping so that multiple processes do
* not try to recycle it.
*/
simple_lock(&vp->v_interlock);
vp->v_usecount--;
if (vp->v_usecount > 0) {
simple_unlock(&vp->v_interlock);
return (error);
}
/*
* insert at tail of LRU list
*/
simple_lock(&vnode_free_list_slock);
if (vp->v_holdcnt > 0)
TAILQ_INSERT_TAIL(&vnode_hold_list, vp,
v_freelist);
else
TAILQ_INSERT_TAIL(&vnode_free_list, vp,
v_freelist);
simple_unlock(&vnode_free_list_slock);
simple_unlock(&vp->v_interlock);
}
return (error);
}
simple_unlock(&vp->v_interlock);
return (0);
}
/*
* vput(), just unlock and vrele()
*/
void
vput(struct vnode *vp)
{
struct proc *p = curproc; /* XXX */
#ifdef DIAGNOSTIC
if (vp == NULL)
panic("vput: null vp");
#endif
simple_lock(&vp->v_interlock);
vp->v_usecount--;
if (vp->v_usecount > 0) {
simple_unlock(&vp->v_interlock);
VOP_UNLOCK(vp, 0);
return;
}
#ifdef DIAGNOSTIC
if (vp->v_usecount < 0 || vp->v_writecount != 0) {
vprint("vput: bad ref count", vp);
panic("vput: ref cnt");
}
#endif
/*
* Insert at tail of LRU list.
*/
simple_lock(&vnode_free_list_slock);
if (vp->v_holdcnt > 0)
TAILQ_INSERT_TAIL(&vnode_hold_list, vp, v_freelist);
else
TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
simple_unlock(&vnode_free_list_slock);
if (vp->v_flag & VEXECMAP) {
uvmexp.execpages -= vp->v_uobj.uo_npages;
uvmexp.filepages += vp->v_uobj.uo_npages;
}
vp->v_flag &= ~(VTEXT|VEXECMAP|VWRITEMAP);
simple_unlock(&vp->v_interlock);
VOP_INACTIVE(vp, p);
}
/*
* Vnode release.
* If count drops to zero, call inactive routine and return to freelist.
*/
void
vrele(struct vnode *vp)
{
struct proc *p = curproc; /* XXX */
#ifdef DIAGNOSTIC
if (vp == NULL)
panic("vrele: null vp");
#endif
simple_lock(&vp->v_interlock);
vp->v_usecount--;
if (vp->v_usecount > 0) {
simple_unlock(&vp->v_interlock);
return;
}
#ifdef DIAGNOSTIC
if (vp->v_usecount < 0 || vp->v_writecount != 0) {
vprint("vrele: bad ref count", vp);
panic("vrele: ref cnt vp %p", vp);
}
#endif
/*
* Insert at tail of LRU list.
*/
simple_lock(&vnode_free_list_slock);
if (vp->v_holdcnt > 0)
TAILQ_INSERT_TAIL(&vnode_hold_list, vp, v_freelist);
else
TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
simple_unlock(&vnode_free_list_slock);
if (vp->v_flag & VEXECMAP) {
uvmexp.execpages -= vp->v_uobj.uo_npages;
uvmexp.filepages += vp->v_uobj.uo_npages;
}
vp->v_flag &= ~(VTEXT|VEXECMAP|VWRITEMAP);
if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK) == 0)
VOP_INACTIVE(vp, p);
}
#ifdef DIAGNOSTIC
/*
* Page or buffer structure gets a reference.
*/
void
vholdl(struct vnode *vp)
{
/*
* If it is on the freelist and the hold count is currently
* zero, move it to the hold list. The test of the back
* pointer and the use reference count of zero is because
* it will be removed from a free list by getnewvnode,
* but will not have its reference count incremented until
* after calling vgone. If the reference count were
* incremented first, vgone would (incorrectly) try to
* close the previous instance of the underlying object.
* So, the back pointer is explicitly set to `0xdeadb' in
* getnewvnode after removing it from a freelist to ensure
* that we do not try to move it here.
*/
if ((vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb) &&
vp->v_holdcnt == 0 && vp->v_usecount == 0) {
simple_lock(&vnode_free_list_slock);
TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
TAILQ_INSERT_TAIL(&vnode_hold_list, vp, v_freelist);
simple_unlock(&vnode_free_list_slock);
}
vp->v_holdcnt++;
}
/*
* Page or buffer structure frees a reference.
*/
void
holdrelel(struct vnode *vp)
{
if (vp->v_holdcnt <= 0)
panic("holdrelel: holdcnt vp %p", vp);
vp->v_holdcnt--;
/*
* If it is on the holdlist and the hold count drops to
* zero, move it to the free list. The test of the back
* pointer and the use reference count of zero is because
* it will be removed from a free list by getnewvnode,
* but will not have its reference count incremented until
* after calling vgone. If the reference count were
* incremented first, vgone would (incorrectly) try to
* close the previous instance of the underlying object.
* So, the back pointer is explicitly set to `0xdeadb' in
* getnewvnode after removing it from a freelist to ensure
* that we do not try to move it here.
*/
if ((vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb) &&
vp->v_holdcnt == 0 && vp->v_usecount == 0) {
simple_lock(&vnode_free_list_slock);
TAILQ_REMOVE(&vnode_hold_list, vp, v_freelist);
TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
simple_unlock(&vnode_free_list_slock);
}
}
/*
* Vnode reference.
*/
void
vref(struct vnode *vp)
{
simple_lock(&vp->v_interlock);
if (vp->v_usecount <= 0)
panic("vref used where vget required, vp %p", vp);
vp->v_usecount++;
#ifdef DIAGNOSTIC
if (vp->v_usecount == 0) {
vprint("vref", vp);
panic("vref: usecount overflow, vp %p", vp);
}
#endif
simple_unlock(&vp->v_interlock);
}
#endif /* DIAGNOSTIC */
/*
* Remove any vnodes in the vnode table belonging to mount point mp.
*
* If FORCECLOSE is not specified, there should not be any active ones,
* return error if any are found (nb: this is a user error, not a
* system error). If FORCECLOSE is specified, detach any active vnodes
* that are found.
*
* If WRITECLOSE is set, only flush out regular file vnodes open for
* writing.
*
* SKIPSYSTEM causes any vnodes marked V_SYSTEM to be skipped.
*/
#ifdef DEBUG
int busyprt = 0; /* print out busy vnodes */
struct ctldebug debug1 = { "busyprt", &busyprt };
#endif
int
vflush(struct mount *mp, struct vnode *skipvp, int flags)
{
struct proc *p = curproc; /* XXX */
struct vnode *vp, *nvp;
int busy = 0;
simple_lock(&mntvnode_slock);
loop:
for (vp = LIST_FIRST(&mp->mnt_vnodelist); vp; vp = nvp) {
if (vp->v_mount != mp)
goto loop;
nvp = LIST_NEXT(vp, v_mntvnodes);
/*
* Skip over a selected vnode.
*/
if (vp == skipvp)
continue;
simple_lock(&vp->v_interlock);
/*
* Skip over a vnodes marked VSYSTEM.
*/
if ((flags & SKIPSYSTEM) && (vp->v_flag & VSYSTEM)) {
simple_unlock(&vp->v_interlock);
continue;
}
/*
* If WRITECLOSE is set, only flush out regular file
* vnodes open for writing.
*/
if ((flags & WRITECLOSE) &&
(vp->v_writecount == 0 || vp->v_type != VREG)) {
simple_unlock(&vp->v_interlock);
continue;
}
/*
* With v_usecount == 0, all we need to do is clear
* out the vnode data structures and we are done.
*/
if (vp->v_usecount == 0) {
simple_unlock(&mntvnode_slock);
vgonel(vp, p);
simple_lock(&mntvnode_slock);
continue;
}
/*
* If FORCECLOSE is set, forcibly close the vnode.
* For block or character devices, revert to an
* anonymous device. For all other files, just kill them.
*/
if (flags & FORCECLOSE) {
simple_unlock(&mntvnode_slock);
if (vp->v_type != VBLK && vp->v_type != VCHR) {
vgonel(vp, p);
} else {
vclean(vp, 0, p);
vp->v_op = spec_vnodeop_p;
insmntque(vp, (struct mount *)0);
}
simple_lock(&mntvnode_slock);
continue;
}
#ifdef DEBUG
if (busyprt)
vprint("vflush: busy vnode", vp);
#endif
simple_unlock(&vp->v_interlock);
busy++;
}
simple_unlock(&mntvnode_slock);
if (busy)
return (EBUSY);
return (0);
}
/*
* Disassociate the underlying file system from a vnode.
*/
void
vclean(struct vnode *vp, int flags, struct proc *p)
{
struct mount *mp;
int active;
LOCK_ASSERT(simple_lock_held(&vp->v_interlock));
/*
* Check to see if the vnode is in use.
* If so we have to reference it before we clean it out
* so that its count cannot fall to zero and generate a
* race against ourselves to recycle it.
*/
if ((active = vp->v_usecount) != 0) {
vp->v_usecount++;
#ifdef DIAGNOSTIC
if (vp->v_usecount == 0) {
vprint("vclean", vp);
panic("vclean: usecount overflow");
}
#endif
}
/*
* Prevent the vnode from being recycled or
* brought into use while we clean it out.
*/
if (vp->v_flag & VXLOCK)
panic("vclean: deadlock, vp %p", vp);
vp->v_flag |= VXLOCK;
if (vp->v_flag & VEXECMAP) {
uvmexp.execpages -= vp->v_uobj.uo_npages;
uvmexp.filepages += vp->v_uobj.uo_npages;
}
vp->v_flag &= ~(VTEXT|VEXECMAP);
/*
* Even if the count is zero, the VOP_INACTIVE routine may still
* have the object locked while it cleans it out. The VOP_LOCK
* ensures that the VOP_INACTIVE routine is done with its work.
* For active vnodes, it ensures that no other activity can
* occur while the underlying object is being cleaned out.
*/
VOP_LOCK(vp, LK_DRAIN | LK_INTERLOCK);
/*
* Clean out any cached data associated with the vnode.
* If special device, remove it from special device alias list.
* if it is on one.
*/
if (flags & DOCLOSE) {
int error;
struct vnode *vq, *vx;
vn_start_write(vp, &mp, V_WAIT | V_LOWER);
error = vinvalbuf(vp, V_SAVE, NOCRED, p, 0, 0);
vn_finished_write(mp, V_LOWER);
if (error)
error = vinvalbuf(vp, 0, NOCRED, p, 0, 0);
KASSERT(error == 0);
KASSERT((vp->v_flag & VONWORKLST) == 0);
if (active)
VOP_CLOSE(vp, FNONBLOCK, NOCRED, NULL);
if ((vp->v_type == VBLK || vp->v_type == VCHR) &&
vp->v_specinfo != 0) {
simple_lock(&spechash_slock);
if (vp->v_hashchain != NULL) {
if (*vp->v_hashchain == vp) {
*vp->v_hashchain = vp->v_specnext;
} else {
for (vq = *vp->v_hashchain; vq;
vq = vq->v_specnext) {
if (vq->v_specnext != vp)
continue;
vq->v_specnext = vp->v_specnext;
break;
}
if (vq == NULL)
panic("missing bdev");
}
if (vp->v_flag & VALIASED) {
vx = NULL;
for (vq = *vp->v_hashchain; vq;
vq = vq->v_specnext) {
if (vq->v_rdev != vp->v_rdev ||
vq->v_type != vp->v_type)
continue;
if (vx)
break;
vx = vq;
}
if (vx == NULL)
panic("missing alias");
if (vq == NULL)
vx->v_flag &= ~VALIASED;
vp->v_flag &= ~VALIASED;
}
}
simple_unlock(&spechash_slock);
FREE(vp->v_specinfo, M_VNODE);
vp->v_specinfo = NULL;
}
}
LOCK_ASSERT(!simple_lock_held(&vp->v_interlock));
/*
* If purging an active vnode, it must be closed and
* deactivated before being reclaimed. Note that the
* VOP_INACTIVE will unlock the vnode.
*/
if (active) {
VOP_INACTIVE(vp, p);
} else {
/*
* Any other processes trying to obtain this lock must first
* wait for VXLOCK to clear, then call the new lock operation.
*/
VOP_UNLOCK(vp, 0);
}
/*
* Reclaim the vnode.
*/
if (VOP_RECLAIM(vp, p))
panic("vclean: cannot reclaim, vp %p", vp);
if (active) {
/*
* Inline copy of vrele() since VOP_INACTIVE
* has already been called.
*/
simple_lock(&vp->v_interlock);
if (--vp->v_usecount <= 0) {
#ifdef DIAGNOSTIC
if (vp->v_usecount < 0 || vp->v_writecount != 0) {
vprint("vclean: bad ref count", vp);
panic("vclean: ref cnt");
}
#endif
/*
* Insert at tail of LRU list.
*/
simple_unlock(&vp->v_interlock);
simple_lock(&vnode_free_list_slock);
#ifdef DIAGNOSTIC
if (vp->v_holdcnt > 0)
panic("vclean: not clean, vp %p", vp);
#endif
TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
simple_unlock(&vnode_free_list_slock);
} else
simple_unlock(&vp->v_interlock);
}
KASSERT(vp->v_uobj.uo_npages == 0);
cache_purge(vp);
/*
* Done with purge, notify sleepers of the grim news.
*/
vp->v_op = dead_vnodeop_p;
vp->v_tag = VT_NON;
simple_lock(&vp->v_interlock);
VN_KNOTE(vp, NOTE_REVOKE); /* FreeBSD has this in vn_pollgone() */
vp->v_flag &= ~(VXLOCK|VLOCKSWORK);
if (vp->v_flag & VXWANT) {
vp->v_flag &= ~VXWANT;
simple_unlock(&vp->v_interlock);
wakeup((caddr_t)vp);
} else
simple_unlock(&vp->v_interlock);
}
/*
* Recycle an unused vnode to the front of the free list.
* Release the passed interlock if the vnode will be recycled.
*/
int
vrecycle(struct vnode *vp, struct simplelock *inter_lkp, struct proc *p)
{
simple_lock(&vp->v_interlock);
if (vp->v_usecount == 0) {
if (inter_lkp)
simple_unlock(inter_lkp);
vgonel(vp, p);
return (1);
}
simple_unlock(&vp->v_interlock);
return (0);
}
/*
* Eliminate all activity associated with a vnode
* in preparation for reuse.
*/
void
vgone(struct vnode *vp)
{
struct proc *p = curproc; /* XXX */
simple_lock(&vp->v_interlock);
vgonel(vp, p);
}
/*
* vgone, with the vp interlock held.
*/
void
vgonel(struct vnode *vp, struct proc *p)
{
LOCK_ASSERT(simple_lock_held(&vp->v_interlock));
/*
* If a vgone (or vclean) is already in progress,
* wait until it is done and return.
*/
if (vp->v_flag & VXLOCK) {
vp->v_flag |= VXWANT;
ltsleep(vp, PINOD | PNORELOCK, "vgone", 0, &vp->v_interlock);
return;
}
/*
* Clean out the filesystem specific data.
*/
vclean(vp, DOCLOSE, p);
KASSERT((vp->v_flag & VONWORKLST) == 0);
/*
* Delete from old mount point vnode list, if on one.
*/
if (vp->v_mount != NULL)
insmntque(vp, (struct mount *)0);
/*
* The test of the back pointer and the reference count of
* zero is because it will be removed from the free list by
* getcleanvnode, but will not have its reference count
* incremented until after calling vgone. If the reference
* count were incremented first, vgone would (incorrectly)
* try to close the previous instance of the underlying object.
* So, the back pointer is explicitly set to `0xdeadb' in
* getnewvnode after removing it from the freelist to ensure
* that we do not try to move it here.
*/
vp->v_type = VBAD;
if (vp->v_usecount == 0) {
boolean_t dofree;
simple_lock(&vnode_free_list_slock);
if (vp->v_holdcnt > 0)
panic("vgonel: not clean, vp %p", vp);
/*
* if it isn't on the freelist, we're called by getcleanvnode
* and vnode is being re-used. otherwise, we'll free it.
*/
dofree = vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb;
if (dofree) {
TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
numvnodes--;
}
simple_unlock(&vnode_free_list_slock);
if (dofree)
pool_put(&vnode_pool, vp);
}
}
/*
* Lookup a vnode by device number.
*/
int
vfinddev(dev_t dev, enum vtype type, struct vnode **vpp)
{
struct vnode *vp;
int rc = 0;
simple_lock(&spechash_slock);
for (vp = speclisth[SPECHASH(dev)]; vp; vp = vp->v_specnext) {
if (dev != vp->v_rdev || type != vp->v_type)
continue;
*vpp = vp;
rc = 1;
break;
}
simple_unlock(&spechash_slock);
return (rc);
}
/*
* Revoke all the vnodes corresponding to the specified minor number
* range (endpoints inclusive) of the specified major.
*/
void
vdevgone(int maj, int minl, int minh, enum vtype type)
{
struct vnode *vp;
int mn;
for (mn = minl; mn <= minh; mn++)
if (vfinddev(makedev(maj, mn), type, &vp))
VOP_REVOKE(vp, REVOKEALL);
}
/*
* Calculate the total number of references to a special device.
*/
int
vcount(struct vnode *vp)
{
struct vnode *vq, *vnext;
int count;
loop:
if ((vp->v_flag & VALIASED) == 0)
return (vp->v_usecount);
simple_lock(&spechash_slock);
for (count = 0, vq = *vp->v_hashchain; vq; vq = vnext) {
vnext = vq->v_specnext;
if (vq->v_rdev != vp->v_rdev || vq->v_type != vp->v_type)
continue;
/*
* Alias, but not in use, so flush it out.
*/
if (vq->v_usecount == 0 && vq != vp &&
(vq->v_flag & VXLOCK) == 0) {
simple_unlock(&spechash_slock);
vgone(vq);
goto loop;
}
count += vq->v_usecount;
}
simple_unlock(&spechash_slock);
return (count);
}
#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
#define ARRAY_PRINT(idx, arr) \
((idx) > 0 && (idx) < ARRAY_SIZE(arr) ? (arr)[(idx)] : "UNKNOWN")
const char * const vnode_tags[] = { VNODE_TAGS };
const char * const vnode_types[] = { VNODE_TYPES };
const char vnode_flagbits[] = VNODE_FLAGBITS;
/*
* Print out a description of a vnode.
*/
void
vprint(const char *label, struct vnode *vp)
{
char bf[96];
if (label != NULL)
printf("%s: ", label);
printf("tag %s(%d) type %s(%d), usecount %d, writecount %ld, "
"refcount %ld,", ARRAY_PRINT(vp->v_tag, vnode_tags), vp->v_tag,
ARRAY_PRINT(vp->v_type, vnode_types), vp->v_type,
vp->v_usecount, vp->v_writecount, vp->v_holdcnt);
bitmask_snprintf(vp->v_flag, vnode_flagbits, bf, sizeof(bf));
if (bf[0] != '\0')
printf(" flags (%s)", &bf[1]);
if (vp->v_data == NULL) {
printf("\n");
} else {
printf("\n\t");
VOP_PRINT(vp);
}
}
#ifdef DEBUG
/*
* List all of the locked vnodes in the system.
* Called when debugging the kernel.
*/
void
printlockedvnodes(void)
{
struct mount *mp, *nmp;
struct vnode *vp;
printf("Locked vnodes\n");
simple_lock(&mountlist_slock);
for (mp = CIRCLEQ_FIRST(&mountlist); mp != (void *)&mountlist;
mp = nmp) {
if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock)) {
nmp = CIRCLEQ_NEXT(mp, mnt_list);
continue;
}
LIST_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes) {
if (VOP_ISLOCKED(vp))
vprint(NULL, vp);
}
simple_lock(&mountlist_slock);
nmp = CIRCLEQ_NEXT(mp, mnt_list);
vfs_unbusy(mp);
}
simple_unlock(&mountlist_slock);
}
#endif
/*
* sysctl helper routine to return list of supported fstypes
*/
static int
sysctl_vfs_generic_fstypes(SYSCTLFN_ARGS)
{
char bf[MFSNAMELEN];
char *where = oldp;
struct vfsops *v;
size_t needed, left, slen;
int error, first;
if (newp != NULL)
return (EPERM);
if (namelen != 0)
return (EINVAL);
first = 1;
error = 0;
needed = 0;
left = *oldlenp;
LIST_FOREACH(v, &vfs_list, vfs_list) {
if (where == NULL)
needed += strlen(v->vfs_name) + 1;
else {
memset(bf, 0, sizeof(bf));
if (first) {
strncpy(bf, v->vfs_name, sizeof(bf));
first = 0;
} else {
bf[0] = ' ';
strncpy(bf + 1, v->vfs_name, sizeof(bf) - 1);
}
bf[sizeof(bf)-1] = '\0';
slen = strlen(bf);
if (left < slen + 1)
break;
/* +1 to copy out the trailing NUL byte */
error = copyout(bf, where, slen + 1);
if (error)
break;
where += slen;
needed += slen;
left -= slen;
}
}
*oldlenp = needed;
return (error);
}
/*
* Top level filesystem related information gathering.
*/
SYSCTL_SETUP(sysctl_vfs_setup, "sysctl vfs subtree setup")
{
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "vfs", NULL,
NULL, 0, NULL, 0,
CTL_VFS, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "generic",
SYSCTL_DESCR("Non-specific vfs related information"),
NULL, 0, NULL, 0,
CTL_VFS, VFS_GENERIC, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "usermount",
SYSCTL_DESCR("Whether unprivileged users may mount "
"filesystems"),
NULL, 0, &dovfsusermount, 0,
CTL_VFS, VFS_GENERIC, VFS_USERMOUNT, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_STRING, "fstypes",
SYSCTL_DESCR("List of file systems present"),
sysctl_vfs_generic_fstypes, 0, NULL, 0,
CTL_VFS, VFS_GENERIC, CTL_CREATE, CTL_EOL);
}
int kinfo_vdebug = 1;
int kinfo_vgetfailed;
#define KINFO_VNODESLOP 10
/*
* Dump vnode list (via sysctl).
* Copyout address of vnode followed by vnode.
*/
/* ARGSUSED */
int
sysctl_kern_vnode(SYSCTLFN_ARGS)
{
char *where = oldp;
size_t *sizep = oldlenp;
struct mount *mp, *nmp;
struct vnode *nvp, *vp;
char *bp = where, *savebp;
char *ewhere;
int error;
if (namelen != 0)
return (EOPNOTSUPP);
if (newp != NULL)
return (EPERM);
#define VPTRSZ sizeof(struct vnode *)
#define VNODESZ sizeof(struct vnode)
if (where == NULL) {
*sizep = (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ);
return (0);
}
ewhere = where + *sizep;
simple_lock(&mountlist_slock);
for (mp = CIRCLEQ_FIRST(&mountlist); mp != (void *)&mountlist;
mp = nmp) {
if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock)) {
nmp = CIRCLEQ_NEXT(mp, mnt_list);
continue;
}
savebp = bp;
again:
simple_lock(&mntvnode_slock);
for (vp = LIST_FIRST(&mp->mnt_vnodelist);
vp != NULL;
vp = nvp) {
/*
* Check that the vp is still associated with
* this filesystem. RACE: could have been
* recycled onto the same filesystem.
*/
if (vp->v_mount != mp) {
simple_unlock(&mntvnode_slock);
if (kinfo_vdebug)
printf("kinfo: vp changed\n");
bp = savebp;
goto again;
}
nvp = LIST_NEXT(vp, v_mntvnodes);
if (bp + VPTRSZ + VNODESZ > ewhere) {
simple_unlock(&mntvnode_slock);
*sizep = bp - where;
return (ENOMEM);
}
simple_unlock(&mntvnode_slock);
if ((error = copyout((caddr_t)&vp, bp, VPTRSZ)) ||
(error = copyout((caddr_t)vp, bp + VPTRSZ, VNODESZ)))
return (error);
bp += VPTRSZ + VNODESZ;
simple_lock(&mntvnode_slock);
}
simple_unlock(&mntvnode_slock);
simple_lock(&mountlist_slock);
nmp = CIRCLEQ_NEXT(mp, mnt_list);
vfs_unbusy(mp);
}
simple_unlock(&mountlist_slock);
*sizep = bp - where;
return (0);
}
/*
* Check to see if a filesystem is mounted on a block device.
*/
int
vfs_mountedon(struct vnode *vp)
{
struct vnode *vq;
int error = 0;
if (vp->v_specmountpoint != NULL)
return (EBUSY);
if (vp->v_flag & VALIASED) {
simple_lock(&spechash_slock);
for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) {
if (vq->v_rdev != vp->v_rdev ||
vq->v_type != vp->v_type)
continue;
if (vq->v_specmountpoint != NULL) {
error = EBUSY;
break;
}
}
simple_unlock(&spechash_slock);
}
return (error);
}
/*
* Do the usual access checking.
* file_mode, uid and gid are from the vnode in question,
* while acc_mode and cred are from the VOP_ACCESS parameter list
*/
int
vaccess(enum vtype type, mode_t file_mode, uid_t uid, gid_t gid,
mode_t acc_mode, struct ucred *cred)
{
mode_t mask;
/*
* Super-user always gets read/write access, but execute access depends
* on at least one execute bit being set.
*/
if (cred->cr_uid == 0) {
if ((acc_mode & VEXEC) && type != VDIR &&
(file_mode & (S_IXUSR|S_IXGRP|S_IXOTH)) == 0)
return (EACCES);
return (0);
}
mask = 0;
/* Otherwise, check the owner. */
if (cred->cr_uid == uid) {
if (acc_mode & VEXEC)
mask |= S_IXUSR;
if (acc_mode & VREAD)
mask |= S_IRUSR;
if (acc_mode & VWRITE)
mask |= S_IWUSR;
return ((file_mode & mask) == mask ? 0 : EACCES);
}
/* Otherwise, check the groups. */
if (cred->cr_gid == gid || groupmember(gid, cred)) {
if (acc_mode & VEXEC)
mask |= S_IXGRP;
if (acc_mode & VREAD)
mask |= S_IRGRP;
if (acc_mode & VWRITE)
mask |= S_IWGRP;
return ((file_mode & mask) == mask ? 0 : EACCES);
}
/* Otherwise, check everyone else. */
if (acc_mode & VEXEC)
mask |= S_IXOTH;
if (acc_mode & VREAD)
mask |= S_IROTH;
if (acc_mode & VWRITE)
mask |= S_IWOTH;
return ((file_mode & mask) == mask ? 0 : EACCES);
}
/*
* Unmount all file systems.
* We traverse the list in reverse order under the assumption that doing so
* will avoid needing to worry about dependencies.
*/
void
vfs_unmountall(struct proc *p)
{
struct mount *mp, *nmp;
int allerror, error;
printf("unmounting file systems...");
for (allerror = 0,
mp = mountlist.cqh_last; mp != (void *)&mountlist; mp = nmp) {
nmp = mp->mnt_list.cqe_prev;
#ifdef DEBUG
printf("\nunmounting %s (%s)...",
mp->mnt_stat.f_mntonname, mp->mnt_stat.f_mntfromname);
#endif
/*
* XXX Freeze syncer. Must do this before locking the
* mount point. See dounmount() for details.
*/
lockmgr(&syncer_lock, LK_EXCLUSIVE, NULL);
if (vfs_busy(mp, 0, 0)) {
lockmgr(&syncer_lock, LK_RELEASE, NULL);
continue;
}
if ((error = dounmount(mp, MNT_FORCE, p)) != 0) {
printf("unmount of %s failed with error %d\n",
mp->mnt_stat.f_mntonname, error);
allerror = 1;
}
}
printf(" done\n");
if (allerror)
printf("WARNING: some file systems would not unmount\n");
}
extern struct simplelock bqueue_slock; /* XXX */
/*
* Sync and unmount file systems before shutting down.
*/
void
vfs_shutdown(void)
{
struct lwp *l = curlwp;
struct proc *p;
/* XXX we're certainly not running in proc0's context! */
if (l == NULL || (p = l->l_proc) == NULL)
p = &proc0;
printf("syncing disks... ");
/* remove user process from run queue */
suspendsched();
(void) spl0();
/* avoid coming back this way again if we panic. */
doing_shutdown = 1;
sys_sync(l, NULL, NULL);
/* Wait for sync to finish. */
if (buf_syncwait() != 0) {
#if defined(DDB) && defined(DEBUG_HALT_BUSY)
Debugger();
#endif
printf("giving up\n");
return;
} else
printf("done\n");
/*
* If we've panic'd, don't make the situation potentially
* worse by unmounting the file systems.
*/
if (panicstr != NULL)
return;
/* Release inodes held by texts before update. */
#ifdef notdef
vnshutdown();
#endif
/* Unmount file systems. */
vfs_unmountall(p);
}
/*
* Mount the root file system. If the operator didn't specify a
* file system to use, try all possible file systems until one
* succeeds.
*/
int
vfs_mountroot(void)
{
struct vfsops *v;
int error = ENODEV;
if (root_device == NULL)
panic("vfs_mountroot: root device unknown");
switch (root_device->dv_class) {
case DV_IFNET:
if (rootdev != NODEV)
panic("vfs_mountroot: rootdev set for DV_IFNET "
"(0x%08x -> %d,%d)", rootdev,
major(rootdev), minor(rootdev));
break;
case DV_DISK:
if (rootdev == NODEV)
panic("vfs_mountroot: rootdev not set for DV_DISK");
if (bdevvp(rootdev, &rootvp))
panic("vfs_mountroot: can't get vnode for rootdev");
error = VOP_OPEN(rootvp, FREAD, FSCRED, curproc);
if (error) {
printf("vfs_mountroot: can't open root device\n");
return (error);
}
break;
default:
printf("%s: inappropriate for root file system\n",
root_device->dv_xname);
return (ENODEV);
}
/*
* If user specified a file system, use it.
*/
if (mountroot != NULL) {
error = (*mountroot)();
goto done;
}
/*
* Try each file system currently configured into the kernel.
*/
LIST_FOREACH(v, &vfs_list, vfs_list) {
if (v->vfs_mountroot == NULL)
continue;
#ifdef DEBUG
aprint_normal("mountroot: trying %s...\n", v->vfs_name);
#endif
error = (*v->vfs_mountroot)();
if (!error) {
aprint_normal("root file system type: %s\n",
v->vfs_name);
break;
}
}
if (v == NULL) {
printf("no file system for %s", root_device->dv_xname);
if (root_device->dv_class == DV_DISK)
printf(" (dev 0x%x)", rootdev);
printf("\n");
error = EFTYPE;
}
done:
if (error && root_device->dv_class == DV_DISK) {
VOP_CLOSE(rootvp, FREAD, FSCRED, curproc);
vrele(rootvp);
}
return (error);
}
/*
* Given a file system name, look up the vfsops for that
* file system, or return NULL if file system isn't present
* in the kernel.
*/
struct vfsops *
vfs_getopsbyname(const char *name)
{
struct vfsops *v;
LIST_FOREACH(v, &vfs_list, vfs_list) {
if (strcmp(v->vfs_name, name) == 0)
break;
}
return (v);
}
/*
* Establish a file system and initialize it.
*/
int
vfs_attach(struct vfsops *vfs)
{
struct vfsops *v;
int error = 0;
/*
* Make sure this file system doesn't already exist.
*/
LIST_FOREACH(v, &vfs_list, vfs_list) {
if (strcmp(vfs->vfs_name, v->vfs_name) == 0) {
error = EEXIST;
goto out;
}
}
/*
* Initialize the vnode operations for this file system.
*/
vfs_opv_init(vfs->vfs_opv_descs);
/*
* Now initialize the file system itself.
*/
(*vfs->vfs_init)();
/*
* ...and link it into the kernel's list.
*/
LIST_INSERT_HEAD(&vfs_list, vfs, vfs_list);
/*
* Sanity: make sure the reference count is 0.
*/
vfs->vfs_refcount = 0;
out:
return (error);
}
/*
* Remove a file system from the kernel.
*/
int
vfs_detach(struct vfsops *vfs)
{
struct vfsops *v;
/*
* Make sure no one is using the filesystem.
*/
if (vfs->vfs_refcount != 0)
return (EBUSY);
/*
* ...and remove it from the kernel's list.
*/
LIST_FOREACH(v, &vfs_list, vfs_list) {
if (v == vfs) {
LIST_REMOVE(v, vfs_list);
break;
}
}
if (v == NULL)
return (ESRCH);
/*
* Now run the file system-specific cleanups.
*/
(*vfs->vfs_done)();
/*
* Free the vnode operations vector.
*/
vfs_opv_free(vfs->vfs_opv_descs);
return (0);
}
void
vfs_reinit(void)
{
struct vfsops *vfs;
LIST_FOREACH(vfs, &vfs_list, vfs_list) {
if (vfs->vfs_reinit) {
(*vfs->vfs_reinit)();
}
}
}
/*
* Request a filesystem to suspend write operations.
*/
int
vfs_write_suspend(struct mount *mp, int slpflag, int slptimeo)
{
struct proc *p = curproc; /* XXX */
int error;
while ((mp->mnt_iflag & IMNT_SUSPEND)) {
if (slptimeo < 0)
return EWOULDBLOCK;
error = tsleep(&mp->mnt_flag, slpflag, "suspwt1", slptimeo);
if (error)
return error;
}
mp->mnt_iflag |= IMNT_SUSPEND;
simple_lock(&mp->mnt_slock);
if (mp->mnt_writeopcountupper > 0)
ltsleep(&mp->mnt_writeopcountupper, PUSER - 1, "suspwt",
0, &mp->mnt_slock);
simple_unlock(&mp->mnt_slock);
error = VFS_SYNC(mp, MNT_WAIT, p->p_ucred, p);
if (error) {
vfs_write_resume(mp);
return error;
}
mp->mnt_iflag |= IMNT_SUSPENDLOW;
simple_lock(&mp->mnt_slock);
if (mp->mnt_writeopcountlower > 0)
ltsleep(&mp->mnt_writeopcountlower, PUSER - 1, "suspwt",
0, &mp->mnt_slock);
mp->mnt_iflag |= IMNT_SUSPENDED;
simple_unlock(&mp->mnt_slock);
return 0;
}
/*
* Request a filesystem to resume write operations.
*/
void
vfs_write_resume(struct mount *mp)
{
if ((mp->mnt_iflag & IMNT_SUSPEND) == 0)
return;
mp->mnt_iflag &= ~(IMNT_SUSPEND | IMNT_SUSPENDLOW | IMNT_SUSPENDED);
wakeup(&mp->mnt_flag);
}
void
copy_statvfs_info(struct statvfs *sbp, const struct mount *mp)
{
const struct statvfs *mbp;
if (sbp == (mbp = &mp->mnt_stat))
return;
(void)memcpy(&sbp->f_fsidx, &mbp->f_fsidx, sizeof(sbp->f_fsidx));
sbp->f_fsid = mbp->f_fsid;
sbp->f_owner = mbp->f_owner;
sbp->f_flag = mbp->f_flag;
sbp->f_syncwrites = mbp->f_syncwrites;
sbp->f_asyncwrites = mbp->f_asyncwrites;
sbp->f_syncreads = mbp->f_syncreads;
sbp->f_asyncreads = mbp->f_asyncreads;
(void)memcpy(sbp->f_spare, mbp->f_spare, sizeof(mbp->f_spare));
(void)memcpy(sbp->f_fstypename, mbp->f_fstypename,
sizeof(sbp->f_fstypename));
(void)memcpy(sbp->f_mntonname, mbp->f_mntonname,
sizeof(sbp->f_mntonname));
(void)memcpy(sbp->f_mntfromname, mp->mnt_stat.f_mntfromname,
sizeof(sbp->f_mntfromname));
sbp->f_namemax = mbp->f_namemax;
}
int
set_statvfs_info(const char *onp, int ukon, const char *fromp, int ukfrom,
struct mount *mp, struct proc *p)
{
int error;
size_t size;
struct statvfs *sfs = &mp->mnt_stat;
int (*fun)(const void *, void *, size_t, size_t *);
(void)strncpy(mp->mnt_stat.f_fstypename, mp->mnt_op->vfs_name,
sizeof(mp->mnt_stat.f_fstypename));
if (onp) {
struct cwdinfo *cwdi = p->p_cwdi;
fun = (ukon == UIO_SYSSPACE) ? copystr : copyinstr;
if (cwdi->cwdi_rdir != NULL) {
size_t len;
char *bp;
char *path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
if (!path) /* XXX can't happen with M_WAITOK */
return ENOMEM;
bp = path + MAXPATHLEN;
*--bp = '\0';
error = getcwd_common(cwdi->cwdi_rdir, rootvnode, &bp,
path, MAXPATHLEN / 2, 0, p);
if (error) {
free(path, M_TEMP);
return error;
}
len = strlen(bp);
if (len > sizeof(sfs->f_mntonname) - 1)
len = sizeof(sfs->f_mntonname) - 1;
(void)strncpy(sfs->f_mntonname, bp, len);
free(path, M_TEMP);
if (len < sizeof(sfs->f_mntonname) - 1) {
error = (*fun)(onp, &sfs->f_mntonname[len],
sizeof(sfs->f_mntonname) - len - 1, &size);
if (error)
return error;
size += len;
} else {
size = len;
}
} else {
error = (*fun)(onp, &sfs->f_mntonname,
sizeof(sfs->f_mntonname) - 1, &size);
if (error)
return error;
}
(void)memset(sfs->f_mntonname + size, 0,
sizeof(sfs->f_mntonname) - size);
}
if (fromp) {
fun = (ukfrom == UIO_SYSSPACE) ? copystr : copyinstr;
error = (*fun)(fromp, sfs->f_mntfromname,
sizeof(sfs->f_mntfromname) - 1, &size);
if (error)
return error;
(void)memset(sfs->f_mntfromname + size, 0,
sizeof(sfs->f_mntfromname) - size);
}
return 0;
}
#ifdef DDB
static const char buf_flagbits[] = BUF_FLAGBITS;
void
vfs_buf_print(struct buf *bp, int full, void (*pr)(const char *, ...))
{
char bf[1024];
(*pr)(" vp %p lblkno 0x%"PRIx64" blkno 0x%"PRIx64" dev 0x%x\n",
bp->b_vp, bp->b_lblkno, bp->b_blkno, bp->b_dev);
bitmask_snprintf(bp->b_flags, buf_flagbits, bf, sizeof(bf));
(*pr)(" error %d flags 0x%s\n", bp->b_error, bf);
(*pr)(" bufsize 0x%lx bcount 0x%lx resid 0x%lx\n",
bp->b_bufsize, bp->b_bcount, bp->b_resid);
(*pr)(" data %p saveaddr %p dep %p\n",
bp->b_data, bp->b_saveaddr, LIST_FIRST(&bp->b_dep));
(*pr)(" iodone %p\n", bp->b_iodone);
}
void
vfs_vnode_print(struct vnode *vp, int full, void (*pr)(const char *, ...))
{
char bf[256];
uvm_object_printit(&vp->v_uobj, full, pr);
bitmask_snprintf(vp->v_flag, vnode_flagbits, bf, sizeof(bf));
(*pr)("\nVNODE flags %s\n", bf);
(*pr)("mp %p numoutput %d size 0x%llx\n",
vp->v_mount, vp->v_numoutput, vp->v_size);
(*pr)("data %p usecount %d writecount %ld holdcnt %ld numoutput %d\n",
vp->v_data, vp->v_usecount, vp->v_writecount,
vp->v_holdcnt, vp->v_numoutput);
(*pr)("tag %s(%d) type %s(%d) mount %p typedata %p\n",
ARRAY_PRINT(vp->v_tag, vnode_tags), vp->v_tag,
ARRAY_PRINT(vp->v_type, vnode_types), vp->v_type,
vp->v_mount, vp->v_mountedhere);
if (full) {
struct buf *bp;
(*pr)("clean bufs:\n");
LIST_FOREACH(bp, &vp->v_cleanblkhd, b_vnbufs) {
(*pr)(" bp %p\n", bp);
vfs_buf_print(bp, full, pr);
}
(*pr)("dirty bufs:\n");
LIST_FOREACH(bp, &vp->v_dirtyblkhd, b_vnbufs) {
(*pr)(" bp %p\n", bp);
vfs_buf_print(bp, full, pr);
}
}
}
void
vfs_mount_print(struct mount *mp, int full, void (*pr)(const char *, ...))
{
char sbuf[256];
(*pr)("vnodecovered = %p syncer = %p data = %p\n",
mp->mnt_vnodecovered,mp->mnt_syncer,mp->mnt_data);
(*pr)("fs_bshift %d dev_bshift = %d\n",
mp->mnt_fs_bshift,mp->mnt_dev_bshift);
bitmask_snprintf(mp->mnt_flag, __MNT_FLAG_BITS, sbuf, sizeof(sbuf));
(*pr)("flag = %s\n", sbuf);
bitmask_snprintf(mp->mnt_iflag, __IMNT_FLAG_BITS, sbuf, sizeof(sbuf));
(*pr)("iflag = %s\n", sbuf);
/* XXX use lockmgr_printinfo */
if (mp->mnt_lock.lk_sharecount)
(*pr)(" lock type %s: SHARED (count %d)", mp->mnt_lock.lk_wmesg,
mp->mnt_lock.lk_sharecount);
else if (mp->mnt_lock.lk_flags & LK_HAVE_EXCL) {
(*pr)(" lock type %s: EXCL (count %d) by ",
mp->mnt_lock.lk_wmesg, mp->mnt_lock.lk_exclusivecount);
if (mp->mnt_lock.lk_flags & LK_SPIN)
(*pr)("processor %lu", mp->mnt_lock.lk_cpu);
else
(*pr)("pid %d.%d", mp->mnt_lock.lk_lockholder,
mp->mnt_lock.lk_locklwp);
} else
(*pr)(" not locked");
if ((mp->mnt_lock.lk_flags & LK_SPIN) == 0 && mp->mnt_lock.lk_waitcount > 0)
(*pr)(" with %d pending", mp->mnt_lock.lk_waitcount);
(*pr)("\n");
if (mp->mnt_unmounter) {
(*pr)("unmounter pid = %d ",mp->mnt_unmounter->p_pid);
}
(*pr)("wcnt = %d, writeopcountupper = %d, writeopcountupper = %d\n",
mp->mnt_wcnt,mp->mnt_writeopcountupper,mp->mnt_writeopcountlower);
(*pr)("statvfs cache:\n");
(*pr)("\tbsize = %lu\n",mp->mnt_stat.f_bsize);
(*pr)("\tfrsize = %lu\n",mp->mnt_stat.f_frsize);
(*pr)("\tiosize = %lu\n",mp->mnt_stat.f_iosize);
(*pr)("\tblocks = "PRIu64"\n",mp->mnt_stat.f_blocks);
(*pr)("\tbfree = "PRIu64"\n",mp->mnt_stat.f_bfree);
(*pr)("\tbavail = "PRIu64"\n",mp->mnt_stat.f_bavail);
(*pr)("\tbresvd = "PRIu64"\n",mp->mnt_stat.f_bresvd);
(*pr)("\tfiles = "PRIu64"\n",mp->mnt_stat.f_files);
(*pr)("\tffree = "PRIu64"\n",mp->mnt_stat.f_ffree);
(*pr)("\tfavail = "PRIu64"\n",mp->mnt_stat.f_favail);
(*pr)("\tfresvd = "PRIu64"\n",mp->mnt_stat.f_fresvd);
(*pr)("\tf_fsidx = { 0x%"PRIx32", 0x%"PRIx32" }\n",
mp->mnt_stat.f_fsidx.__fsid_val[0],
mp->mnt_stat.f_fsidx.__fsid_val[1]);
(*pr)("\towner = %"PRIu32"\n",mp->mnt_stat.f_owner);
(*pr)("\tnamemax = %lu\n",mp->mnt_stat.f_namemax);
bitmask_snprintf(mp->mnt_stat.f_flag, __MNT_FLAG_BITS, sbuf,
sizeof(sbuf));
(*pr)("\tflag = %s\n",sbuf);
(*pr)("\tsyncwrites = " PRIu64 "\n",mp->mnt_stat.f_syncwrites);
(*pr)("\tasyncwrites = " PRIu64 "\n",mp->mnt_stat.f_asyncwrites);
(*pr)("\tsyncreads = " PRIu64 "\n",mp->mnt_stat.f_syncreads);
(*pr)("\tasyncreads = " PRIu64 "\n",mp->mnt_stat.f_asyncreads);
(*pr)("\tfstypename = %s\n",mp->mnt_stat.f_fstypename);
(*pr)("\tmntonname = %s\n",mp->mnt_stat.f_mntonname);
(*pr)("\tmntfromname = %s\n",mp->mnt_stat.f_mntfromname);
{
int cnt = 0;
struct vnode *vp;
(*pr)("locked vnodes =");
/* XXX would take mountlist lock, except ddb may not have context */
LIST_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes) {
if (VOP_ISLOCKED(vp)) {
if ((++cnt % 6) == 0) {
(*pr)(" %p,\n\t", vp);
} else {
(*pr)(" %p,", vp);
}
}
}
(*pr)("\n");
}
if (full) {
int cnt = 0;
struct vnode *vp;
(*pr)("all vnodes =");
/* XXX would take mountlist lock, except ddb may not have context */
LIST_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes) {
if (!LIST_NEXT(vp, v_mntvnodes)) {
(*pr)(" %p", vp);
} else if ((++cnt % 6) == 0) {
(*pr)(" %p,\n\t", vp);
} else {
(*pr)(" %p,", vp);
}
}
(*pr)("\n", vp);
}
}
#endif /* DDB */
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